Methods and apparatus for producing intermittently elasticized yarns



July 2, 1963 E. H. PITTMAN 3,095,630

METHODS AND APPARATUS FOR PRODUCING INTERMITTENTLY ELASTICIZED YARNS Filed Nov. 12, 1959 INVENTOR.

EDGAR HENRY P/TTMA/V.

United States Patent Ofi ice Patented July 2,v 1963 3,095,630 METHODS AND APPARATUS FOR PRODUCING INTERMITTENTLY ELASTICIZED YARNS Edgar Henry Pittman, Sp'artanburg, S.C., assignor to Deering Milliken Research Corporation, Spartanburg, S.C.,

a corporation of Delaware Filed Nov..12, 1959, Ser. No. 852,508 r 9 Claims. (Cl. 28 1) This invention relatesto novel intermittently elasticized and heat treated yarn and to .a novel method and apparatus for producing such yarn. V

' According to this invention a novel texturized continuous filament yarn of thermoplastic material, such as nylon, Dacron, etc., is produced having linearly alternately elasticized heat relaxed and shrunk segments and segments which are substantially only partially elasticized and heat relaxed or substantially non-elasticized and non-heat relaxed. This novel yarn is produced according to the invention through the passage of continuous filament thermoplastic yarn through a heating zone and then over a relatively cold,, sharp-edged surface to impart a substantially permanent latent crimp thereto, and intermittently substantially reducing the application of heat to the yarn prior to passage over the sharp edge. 'In the illustrated embodiment this reduction in the amount of heat imparted to the yarn is effected mechanically through the mediumf of a lifter arm which is moved intermittently to raise the yarn on of a contact heaterstrip over which the yarn normally passes in engagement prior to passing over the sharp edgeof a blade. This intermittent movement of the lifter arm and yarn may be effected in any desired manner and'may be accomplished at periodic intervals or preferably at random intervals. The yarn which. is processedlaccording to this method maybe single filament 'or preferably multi filament synthetic thermoplastic ma- -terial of any desired content or blend, including nylon, Dacron, etc; nylon being the preferred yarn material. The novel yarn produced according to this invention will have alternate segments which are respectively both heat relaxed and permanently cn'mped (the crimp being substantially latent prior to development thereof by subsequent crimp developing treatment), corresponding to the segments which have fully engaged both the heater strip and the sharp blade edge, and substantially non-heatpreferably agitated in a bath of liquid, such as water,

I the invention is illustrated in the accompanying drawings wherein:

FIGURE 1 is a schematic illustration in perspective of a single yarn processingv position according to the invention, showing the normal heat setting and crimping position of the apparatus and yarn in full lines and the reduced heat setting and crimping position'of the apparatus and yarn in; broken lines, i

FIGURE 2'is a schematic illustration of a fully developed length of yarn according to the invention.

FIGURE 3 is a schematic view in perspective of a I fabric constructed of yarn according to the invention, the

.relaxed or substantially lessheat relaxed segmentshaving only a'partial or substantially no permanent crimp therein, corresponding to the segments which have passed over the blade-edge with substantially less or no conta'ctwith the heater (Le. which pass over the blade at a substantially colder temperature than the-other substantially preheated segments of yarn). This yarn is particularly advantageous ,in. providing novel design effects in fabrics which may be woven or knit therefrom. The latent crimp in the heat relaxed and permanently crimped segments and the shrinkage. remainingin the ,un-heat relaxed segments may be subsequently developed in any suitable manner as by subjectingtheyarn to hot moisture, hot air, or contact heatertrea'tment, either before formation of a fabric therefrom or after formation of a fabric. If developed prior .toformation'of a fabric therefrom, the yarn maybe heat I developed in a substantially loose untensioned condition in' orderito'npermit maximum crimp development in the .iheatxrelaxed 'andr latently crimpedsegments. It will be apparent lthat with maximum crimp devel'opment in this zifashion, the un-heatrelaxed and uncrimped segments will -likewise be. shrunk to a substantially maximum degree. =iLQf" course, one. might develop the yarn to any lesser sexten't, asdesired, before forming into a fabric, in order "to. achieve ditferientxeffects in Ithelfabri'c after full developyarn having been developed after formation of the fabric.

FIGURE 4 is a schematic section View illustrating the general appearance of the edge of the fabric along line Referring now in detail to the figures of the drawing, a thermoplastic yarn is progressed from a suitable yarn supply such as a bobbin or pirn 11 through a suitable guide arrangement 13 and ten'sioning device 15, through an intermittent texturizing device generally indicated at 17, and thence to a takeup device such as a ring and traveler twister takeup 18.

The yarn texturizing device 17 includes a yarn heating element in the form of .a heater strip 19 over which the yarn Y normally passes in substantial'contact, a sharpedged crimping element in the form of a sharp edged (e.g.

edge radius of approximately 001-0003) blade 21 over which the yarnfis passed througha relatively sharp approach and return angle subsequent to passage over the adjacent the heater and blade assembly, and extends rearwardly to a point behind the heater strip 19. The lifter arm 25 has an outer transverse end 25a which is formed for engagement beneath the yarn Y to lift the yarn during clocl wise pivotal movement of the pivot shaft 27 and arm 25 as viewed in the figure. This raising of the yarn lifter arm 25may be effected through any desired angle, and the angle may be'varied to effect a desired amount of lifting of the yarn oflf "the heater. It is normally preferred A 'Dhe lifter arm maybe raised andlowered in any suit- 'ment therein. When developed inthe fabric the fabric is to raise the arm substantially completely off the heater in .order to effect the greatest differentiation inthe alternate segments of the yarn,,,although it willbe apparent'that in some instances it 'Will be desirable to raise the yarn by a lesser amount, thereby onlyidecreasing the amount of heat imparted thereto by the heater strip and effecting a less pronounced diiferentiation between the alternate seg ments of the yaru.

able manner at intermittent intervals which may be either periodic orpreferablyjrandom. nine. illustrated en1- bodirnent the-lifter airm 25-is raised and lowered by imparting an oscillating motion to the shaft 27 through the medium of a solenoid 31 and return spring 33 con- ;nected in. opposing relation to a lever arrn35 secured to the shaft, The armature31a of the solenoid is suitably connected tothe lever arm 35 and exerts a pull thereon tolower, the lifter arm 25 and the yarn to its full heater engaging position when the solenoid is energized as by any suitable intermittent signal generating device 37, and the arm 25 is raised under the influence of the return spring 33 to return the yarn upon the cessation of the electrical signal impulse to the solenoid. The angle of movement of the lifter arm may be restricted by the engagement of the solenoid armature 31a with the opposite ends of the solenoid coil winding casing 31b, or other stops may be suitably employed to effect this limiting action on the lifter arm movement if desired.

In processing the yarn according to the present invention, I have found that the tension of the yarn may be varied over a substantial range dependent upon the denier of the yarn and the number of filaments therein, as well as the particular material of the yarn. In carrying out the invention with the illustrated apparatus I have noted that the tension of the yarn while fully engaging the heater is normally lower than the tension of the yarn in the raised position. For example, the tension of the yarn on the output side of the blade 21 when the yarn is engaged fully on the heater in the normally running position may be between 5-7 grams for 30 denier, filament, nylon yarn, with the tension of the yarn in the raised position being 8-l0 grams or the like, this being merely by way of illustration. In order to accentuate the pattern differentiation between the treated and substantially untreated segments of the yarn the tension may be increased. In order to effect substantially permanent crimp in the heated segments 41, the temperature of the heater strip 19 should be sufficiently high to raise the temperature of the yarn Y or at least the surface temperature of the yarn to a point between the second order transition point and the first order transition point for the particular yarn being run. This temperature in the yarn may normally be obtained by maintaining the heater strip at a temperature approximately the same as or slightly higher than the temperature to which it is desired to heat the yarn While in contact therewith, depending upon the rate of yarn travel therepast.

In FIGURE 2 there is schematically shown a single multi-filament yarn which has been processed according to the present invention and which has been subjected to a full development of the latent bulk and crimp imparted to the yarn by the intermittent bulking and crimping apparatus as described above. The bulked and crimped portions of the yarn are indicated by the numeral 41, whereas the substantially unbulked and uncrimped portions of the yarn are indicated at 43. The bulked portions correspond to those incremental segments of the yarn wherein the yarn removal arm is in the nonremoving portion and the initial portions of its removing and replacing portion, whereas the substantially nonbulked and noncrimped portions of the yarn represent those incremental segments which have been passed through the apparatus while the yarn removal arm is in a position to effect substantially full removal of the yarn from the heater. It will be noted that there is a gradual change between the maximum crimped and bulked portions of the segments 41 and the adjacent substantially uncrimped and unbulked incremental segments 43. This results from the fact that there is not an immediate change from full engagement to substantially no engagement of the yarn with the heater, inasmuch as there is a time element involved in raising and lowering the yarn by the yarn removal arm away from and toward the heater, and during this time the yarn continues to progress over the heater and adjacent sharp edge. It will be apparent, however, that while gradual'ch-ange is often desirable, and is the preferred form of practice of the invention, the invention may also be practiced by substantially full removal of the yarn from the heater element with comparatively little transition time lapse during removal and replacement, in order to effect a comparatively abrupt dilferential between the heat-set, elasticized, and bulked incremental segments and the substantially unbulked and unheat-set segments.

In FIGURE 3 there is schematically illustrated a fabric F which has been formed of a yarn according to the present invention, the fabric having been made from the yarn prior to development of the yarn and the yarn having been developed after formation of the fabric. Due to this subsequent development of the yarn in situ in the fabric there is both a development of bulk and elasticity of the yarn in those incremental segments 41 which were passed over the blade in substantially heated relation as a result of being in substantial contact with the heater, and also a creping effect imparted to the fabric areas having these segments therein as a result of heat shrinkage of the basically unheated treated incremental segments 43 which did not receive any substantial heat development during their passage about the heater element. The elasticized and bulked segments are indicated in the fabric at 41a by the raised and more bulky areas, and it will be noticed that the appearance of the creping or wrinkles 41a in the face of the fabric is enhanced by the relatively flat areas 43 where the yarn segments 43 lie. While this one particular embodiment of a fabric is illustrated, it will be understood that this is only by way of example, and that many other constructions might be made Within the scope of the invention, such as the development of the yarn prior to formation in the fabric, the formation of the fabric with the yarn in both the warp and the filling, etc.

While this invention has been illustrated and described with reference to a single physical embodiment of an apparatus for practice thereof, it will be readily apparent to those skilled in the art from a reading of the foregoing description that many modifications and improvements may be made without departing from the scope and spirit of the invention. It is therefore to be understood that the invention is not to be limited to the presently illustrated embodiment but only by the scope of the appended claims.

That which is claimed is:

1. The method of processing thermoplastic yarn comprising heating said yarn and passing said yarn in a heated state over and past a sharp-bend surface with a sharp angle of bend in the path of said yarn as it passes over said bend surface, and intermittently altering the degree of heating of said yarn substantially immediately preceding passage over said bend surface whereby succeeding increments of yarn passing over said bend surface are at different temperatures as they pass over said bend surface and are thereby differentially crimp-modified.

2. The method according to claim 1 wherein said yarn is heated by contact with a heat source in preceding flow relation to said passage over said sharp bend surface, said intermittent altering of said heating being effected by intermittently altering the degree of contact of said yarn with said contact heat source.

3. The method according to claim 2 wherein said yarn is intermittently moved in a direction transverse to its normal linear progression path and in a direction toward and away from said contact heat source.

4. The method according to claim 1 wherein said intermittent altering of heating is random.

5. The method according to claim 1 wherein said intermittent altering of heating is periodic.

6. Apparatus for processing thermoplastic textile yarn comprising a yarn supply source, a yarn take-up, a yarn crimping device disposed in intermediate flow relation between said supply means and said take-up means, said yarn crimping means comprising a sharp-bend crimping element disposed in yam-bending relation at a point along the path of said yarn, heater means disposed in substantially immediate preceding flow relation to said yarn crimping element, and means for intermittently altering the degree of heating of said yarn by said heating means whereby succeeding increments of yarn passing over said sharp-bend crimping element are at different temperatures as they pass in a sharp bend over said element and are thereby difiterentially crimp-modified.

7. Apparatus according to claim 6 wherein said heating means is a contact heater arranged in contact flow relation in the normal path of said yarn, said means for intermittently altering the degree of heating of said yarn comprising a yarn-moving member movable transversely to the normal path of said yarn past said contact heater and in a direction toward and away from said heater.

8. Apparatus according to claim 7 wherein said yarnmoving member comprises a pivotally mounted arm disposed adjacent said contact heater and means for selectively intermittently imparting movement to said arm.

9. The method of processing thermoplastic yarn comprising heating said yarn and passing said yarn in a heated state over and through a sharp angle of bend, and intermittently altering both the degree of heating of said yarn and the angle of bend thereof, to thereby differentially crimp modify said yarn as a combination function of both the differential angle of bend and differential degree of heating of the yarn.

References Cited in the file of this patent UNITED STATES PATENTS Taylor et a1 Dec. 15, Me-loon Sept. 22, Lodge Aug. 24, Ladisch Oct. 7, Ladisch Apr. 6, Gayler Oct. 26, Iwamae Nov. 2, Vandamme et a1. Feb. 5, Matthews et a1 Mar. 3, Braunlich July 14, Dyer Jan. 12, Comer et a1 J an. 24, Davenport et a1. Sept. 12,

FOREIGN PATENTS Australia Feb. 9, Austria May 25, Great Britain Dec. 30, Great Britain Sept. 10, 

1. THE METHOD OF PROCESSING THERMOPLASTIC YARN COMPRISING HEATING SAID YARN AND PASSING SAID YARN IN A HEATED STATE OVER AND PAST A SHARP-BEND SURFACE WITH A SHARP ANGLE OF BEND IN THE PATH OF SAID YARN AS IT PASSES OVER SAID BEND SURFACE, AND INTERMITTENTLY ALTERNING THE DEGREE OF HEATING OF SAID YARN SUBSTANTIALLY IMMEDIATELY PRECEDING PASSAGE OVER SAID BEND SURFACE WHEREBY SUCCEEDING INCREMENTS OF YARN PASSING OVER SAID BEND SURFACE ARE AT DIFFERENT TEMPERATURES AS THEY PASS OVER SAID BEND SURFACE AND ARE THEREBY DIFFERENTIALLY CRIMP-MODIFIED.
 6. APPARATUS FOR PROCESSING THERMOPLASTIC TEXTILE YARN COMPRISING A YARN SUPPLY SOURCE, A YARN TAKE-UP, A YARN CRIMPING DEVICE DISPOSED IN INTERMEDIATE FLOW RELATION BETWEEN SAID SUPPLY MEANS COMPRISING A SHARP-BEND CRIMPING YARN CRIMPING MEANS COMPRISING A SHARP-BEND CRIMPING ELEMENT DISPOSED IN YARN-BENDING RELATION AT A POINT ALONG THE PATH OF SAID YARN, HEATER MEANS DISPOSED IN SUBSTANTIALLY IMMEDIATE PRECEDING FLOW RELATION TO SAID YARN CRIMPING ELEMENT, AND MEANS FOR INTERMITTENTLY ALTERNING THE DEGREE OF HEATING OF SAID YARN BY SAID HEATING MEANS WHEREBY SUCCEEDING INCREMENTS OF YARN PASSING OVER SAID SHARP-BEND CRIMPING ELEMENT ARE AT DIFFERENT TEMPERATURES AS THEY PASS IN A SHARP BEND OVER SAID ELEMENT AND ARE THEREBY DIFFERENTIALLY CRIMP-MODIFIED. 